Avian influenza risk to Australian poultry industry from free range farm practices

Abstract

Purpose: The 7 highly pathogenic AI outbreaks in Australia since 1976 all involved non-exotic H7 and caused clinical disease on commercial poultry farms. The two most recent outbreaks in 2012-2013 involved a farm with all/ some of the layer flock under free-range management. Industry concern about the AI risk posed by free-range farms arises from some practices on these farms (eg access to range) and evidence from wild bird surveillance of low pathogenic AI virus (including H5 and H7) present in 25 species of Australian birds, mostly native duck and coot species. However there are limited data to inform the actual risk for AI virus introduction posed by free-range management under Australian conditions.